My 1982 300D leaves a cloud of smoke when I really step on the pedal. The smoke is not really thick, you can see through it, not heavy black like some trucks I have seen. It is very visible in late afternoon when the sun is lower in in the sky. Yesterday I left a large cloud of smoke when I jetted (if you can call it Jetting in a 300D) across the road. It was still hanging in the air after I turned and looked back. I changed the air filter and that did not make any difference. I am thinking maybe the EGR valve or timing? Thanks for any help.

Sounds kinda normal to leave a puff of black smoke behind at takeoff, especially if you've messed with / removed ALDA.

If you continue to stream black smoke on the highway, under heavy pedal, then maybe your problem is insufficient air (lack of turbo pressure). Temporarily block your EGR, then leave it blocked. Bad timing smoke usually shows up more at start-up. Maybe you're sucking in oil that shouldn't be... turbo seal, PCV system, etc. Check the intake manifold runners, check blow-by.

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Cheers!
Scott McPhee

1987 300D

A bunch of stuff can have that effect. Gray to black smoke is incomplete combustion.

Some other things:
Engine operating Temp not hot enough
Worn out of spec Injectors not atomizing the Fuel well
Valves out of adjustment
Engine Compression going south due to wear or stuck Rings
Is there a lot of Blowby that could be burning in the Cylinders

I do not know the symptoms of a stretched Timing Chain before it gets to the point that it causes somethings to hit something. Maybe someone would comment on that. It would cause late Valve and IP Timing if it had not be compensated for.

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84 300D, 82 Volvo 244Gl Diesel

Sounds pretty normal to me too. Every diesel I've ever seen smokes some on takeoff. The ones that don't show it are just hiding it in a recirculation system or a trap or something.

Both of mine do it, and I'm not concerned. My $0.02

There's some extreme things (injector maintenance, fuel additives, fuel reduction (horsepower reduction as well) that can reduce it, but... why bother? Just tells you your engine's giving you all the power it's capable of, which under acceleration is exactly what you want. They're borderline anemic as it is, might as well get all they've got to give.

If it doesn't smoke a little at takeoff, you aren't delivering as much fuel as you could potentially burn (therefore making horsepower) at that moment. You don't want it to smoke constantly of course. But that "threshold" between full acceleration producing no smoke and just a tad of smoke represents the border at which you are consuming as much fuel as the cylinders can burn, and making the most power the cylinders can produce. Extra smoke on top of this is wasted fuel. Not reaching this point is wasted horsepower potential on an already none-too-speedy engine. (Don't get me wrong. My 603 is fast enough to get a ticket just like anything else. But they're no V8s off the line.)

A *tad* too much smoke is better than none at all in this case, and the measures that have to be taken to reduce it are usually pretty extensive.

That being said... it's *possible* that what someone said about injectors being dirty and poorly adjusted causing incomplete combustion -- is what is happening in your case. If that's true, then it's probably worth having the injectors adjusted at some point in the future just to get everything clean and optimal. However... it's certainly no emergency. The smoke is not symptomatic of anything "wrong". At worst, just something that "could be better but isn't hurting anything."

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~Michael S.~
Past cars:

1986 300SDL
1987 300SDL
1982 240D
1982 300SD


Current:

1987 300SDL

[QUOTE=bustedbenz;2482293]Sounds pretty normal to me too. Every diesel I've ever seen smokes some on takeoff. The ones that don't show it are just hiding it in a recirculation system or a trap or something.

Both of mine do it, and I'm not concerned. My $0.02
QUOTE]

X2. There seems to be more from my 617 when it's put on several miles just lugging around town. A good highway run will reduce it for awhile.
I find I can increase the amount of smoke by downshifting. This I do when being tailgated - they are usually quick to back off or pass me by!

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Charles
1983 300D, bought new, 215k+ miles, donated to Purple Hearts veterans charity but I have parts for sale: http://www.peachparts.com/shopforum/showthread.php?t=296386

I also love "blowing coal" its fun to remind your self and others that your car is a diesel. I would only get worried if it happend for long periods of time while cruzing. White=coolant, Blue/Gray=oil, Black=fuel. General rule of thumb.

I think of it as a built-in defense mechanism against tailgating white BMW sportscars. Especially when they're riding your bumper right through a downtown street where it's not safe to speed for fear of police.

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~Michael S.~
Past cars:

1986 300SDL
1987 300SDL
1982 240D
1982 300SD


Current:

1987 300SDL

That's what diesels do, spew out smoke! Check these out:
http://www.youtube.com/watch?v=ep-soNJ8D8Y
http://www.youtube.com/watch?v=ixERCJfGyeY&feature=related
I bet you don't get smoke THAT thick

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[/SIGPIC]~cirrusman

1983 Mercedes Benz 300SD - Wife calls him "Chitty Chitty Bang Bang"
[SIGPIC]




1983 Toyota Tercel (Tommy, The little Toyota that could)
1965 Ford F100 (Grandma Ford)
2005 Toyota Sienna (Elsa, Wife's ride)


Gone:
1988 Toyota Pickup
2004 Subaru Outback

1987 Cadillac Fleetwood Brougham
1986 Volvo 740 GL Station Wagon - Piece of junk.
1981 Volvo 242 DL 2 Door - Hated to see it go. R.I.P.
1987 Pontiac Fiero GT